Internships/ProjectIdeas/Microbit

micro:bit machine type

Summary: Add emulation support for the micro:bit board

The micro:bit is a small computer for educational use that is also suitable for embedded and Internet of Things (IoT) projects. It uses a 16 MHz ARM Cortex-M0 processor with 256 KB flash and 16 KB RAM. It features many I/O capabilities including a 5x5 LED display, 2 buttons, Bluetooth and Nordic Gazell radio communications, an accelerometer, a compass, temperature and light sensing, UART, and GPIO pins for external devices.

This project will add micro:bit emulation support to QEMU, allowing code written with the Python and Javascript Blocks editors to run on your computer. Baremetal code not written with the official editors, such as C/C++ code using the microbit-dal runtime, will also work since QEMU emulates a full system including CPU and hardware devices.

This project involves:

1. Implementing ARM Cortex-M0 CPU support based on existing Cortex-M3 support in QEMU
2. Implementing a micro:bit .hex ROM loader
3. Implementing a "microbit" machine type
4. Implementing at least the 5x5 LED display, buttons, and UART.
5. Stubbing out other devices as needed for the runtime to start successfully.

The goal is to run "Hello World!" programs created with the Python and Javascript Blocks editors. If you have time it may be possible to implement additional hardware devices or a graphical user interface.

Previous experience with low-level systems software (firmware, bootloaders, kernels) and hardware (Arduino, PIC, microcontrollers) is recommended. Start by looking at the reference design schematic to understand how the micro:bit works.

Links:

• Hardware specifications
• Reference design hardware schematic
• microbit-dal runtime

Details:

• Skill level: advanced
• Language: C
• Mentors: Stefan Hajnoczi <stefanha@gmail.com> ('stefanha' on IRC), Jim Mussared <jim@groklearning.com>, Joel Stanley <joel@jms.id.au>